Lubricant producing system



y 1970 E. J. BRETON ETAL 3,513,084

LUBRICANT PRODUCING SYSTEM Filed June 28, 1968 2 Sheets-Sheet l FIG-1LOAD F I G- 2 2 s1 65 I I z INVENTORS ERNEST J. BRETON {a 1 CURTIS B.CAMERON M ROBERT ELMURVINE May 19, 1970 E. J. BRETON E-TAL 3,513,084

LUBRICANT PRODUCING SYSTEM Filed June 28, 1968 2 Sheets-Sheet 2 2e fi 34:33 GI 3 4o i 23 I 21 22 24 m LLLL 1 INVENTORS ERNEST J. BRETON CURTISB. CAMERON ROBERT E. MURVINE United States Patent "ice 3,513,084LUBRICANT PRODUCING SYSTEM Ernest J. Breton and Curtis B. Cameron,Wilmington, and

Robert E. Murvine, Newark, Del., assignors to E. I. du

Pont de Nemours and Company, Wilmington, Del., a

corporation of Delaware Filed June 28, 1968, Ser. No. 740,880 Int. Cl.Cg 41/00; C08f 1/02; C08g 35/00 US. Cl. 208-46 35 Claims ABSTRACT OF THEDISCLOSURE One can avoid the necessity of adding lubricants to a varietyof fluid process assemblies involving relatively movable opposingsurfaces by selecting the composition of the opposing surfaces.Specifically, the lubricant can be formed in situ from the fluid usedwhere one surface is of a mixture of an alloy containing at least 6 atompercent of an element selected from the group consisting of molybdenumand tungsten, at least 10 percent by volume of the alloy being anintermetallic compound of molybdenum or tungsten having a VickersHardness number of 550-1800, and a softer material that is strong enoughto support'the alloy particles in the shape required for use; the matingsurface is either of an alloy containing at least 50 atom percent iron,at least 1 atom percent carbon, at least one-half the weight of theremainder of the alloy being composed of at least one of the followingelements: chromium, manganese, molybdenum and tungsten, said element(s)being present as carbide(s) or in a fully hardened solid solution, andhaving a Vickers Hardness number of at least 400 or a similar alloycontaining at least 80 atom percent iron and having a Vickers Hardnessnumber of at least 200 or an alloy of 11-15 atom percent carbon, 1.5-3atom percent silicon, the balance being iron, having a Vickers Hardnessnumber of at least 150*; and the fluid is an organic compound capable ofpolymerizing to form a lubricant, e.g., petroleum hydrocarbons,aliphatic alcohols, and aliphatic aldehydes having at least 4 carbonatoms. Although one can obtain a useful lubricating system using thealloy of molybdenum or tungsten as the first surface and one of thealloys of iron as the second surface, a substantial improvement isobtained by using the mixtures set forth herein as the first surface.

Cross references to related applications This application is related tothe copending application, Ser. No. 780,879, entitled LubricantProducing System which was filed on the same date as the presentapplication.

Background of the invention This invention is in the field of functionalsystems producing lubrication.

Ideally, a lubricant for the interface of relatively movable (sliding,rubbing, rolling, etc.) opposing surfaces should serve to completelyseparate those surfaces. This condition is known as full-film orhydrodynamic lubrication. Full-film lubrication physically separates thetwo sliding surfaces by a relatively thick continuous film ofself-pressurized lubricant with no metal-to-metal contact.Technologically, this is the preferred kind of lubrication since itoffers the lowest coefficient of friction and the smallest amount ofWear.

When the two sliding surfaces are being rubbed together in the presenceof an extremely thin film of lubricant which adheres to both surfaces,this condition is known as complete boundary lubrication. Unless thelubricant is renewed periodically, the thin film is eventually destroyedand intimate metal-to-metal contact re- Patented May 19, 1970 sults (dryoperation) with the result being scoring and galling of the metals, andeventually seizure.

A transitional zone known as mixed-film lubrication is a combination ofhydrodynamic and boundary lubrication. Under this condition, part of thetotal load applied to an opposing metal surface is supported byindividual load-carrying areas of self-pressurized lubricant and theremaining part by the very thin film associated with boundarylubrication.

Under full-film conditions, the coeflicient of fluid friction isapproximately proportional to viscosity and speed and inverselyproportional to load. Where true boundary lubrication exists, thecoefiicient of friction is independent of viscosity and rubbing speed.Thus for small values of ZN/ p, where Z is the viscosity of the inputfluid, N is rotational speed and p is bearing pressure (load), thecoefficient of friction remains essentially constant. Between theboundary and full-film zones of lubrication is the zone where, withreduction of ZN/p, the coeflicient of friction increases sharply.Evidence indicates that in this zone a combination of fluid friction andboundary lubrication exists, i.e., mixed-film lubrication.

When the speed (N) and viscosity (Z) are low, the load, which can beapplied to surfaces without attaining unduly high coefiicients offriction and the resultant catastrophic effects thereof, mustnecessarily be. very low Hence, the use of low viscosity fluids aslubricants is precluded in most industrial applications since their useplaces a severe restriction on the load bearing capacity.

Lubrication of the opposing surfaces of seals, gears, bearings andpistons, therefore, has required the use of more viscous materials suchas hydrocarbon oils, synthetic oils and greases. These lubricants, inaddition to being incapable of being tolerated in certain applicationsbecause of process contamination, possess other disadvantages. Whenthese lubricants are used continuously over extended periods at highpressures and elevated temperatures, they tend to deteriorate. Sludgestend to form in the lubricants as a result of oxidation, polymerization,or other causes. These sludges reduce the lubricating qualities of thelubricant and often cause sticking of relatively moving parts. Inaddition, organic acids tend to form in the lubricant during usethereof, apparently because of oxidation of the oil at the elevatedtemperatures to which the oil is exposed, and organic acids causecorrosion.

Additional disadvantages exist where the operation of engines requiremixing oil with the fuel as in the Z-cycle engine and the epitrochoidalrotary engines. Smoke, fouling of the spark plugs, sticking of pistonrings, and carbon deposits result from the use of such mixtures.

It is apparent that great advantages could be obtained if the processfluid, e.g., gasoline in internal combustion engines, could itself beused for lubricating the opposing parts. Besides eliminating the needfor auxiliary systems for handling lubricant, the use of the processfluid for lubrication could lead to improved reliability and reductionin the size, weight and cost of the apparatus. Additionally, since thesefluids are being continuously used up in the operation of the particularprocess, contamination by such things as sludge formation would beminimized.

It is, therefore, the object of this invention to provide assembliescomposed of sleeve bearings, seals, sliding vanes, pistons, pistonrings, etc. moving against opposing surfaces that will function in thepresence of low viscosity organic agents. It is another object toprovide an assembly capable of converting in situ a low viscosityorganic fluid, e.g., gasoline vapor or liquid, unsuitable as a lubricantin its unpolymerized state to a more viscous polymeric materialcharacterized by its ability to maintain a state of boundary lubricationor full-film lubrication during periods of operation. It is a furtherobject to provide lubricant-producing assemblies for designing andconstructing devices (engines, pumps, etc.) in which the problemsresulting from the conventional use of lubricants are eliminated.

Summary of invention The objects are accomplished according to thepresent invention by an assembly comprising at least two members havingrelatively movable opposing surfaces, members A and B, and a fluidcapable of polymerizing to form a lubricant during operation of theassembly (a lubricant precursor); the metal-opposing surface of member Acomprising an alloy selected from the group consisting of (a) an alloyof 11-15 atom percent carbon, 1.5-3 atom percent silicon and the balancebeing substantially all iron, and having a Vickers Hardness number of atleast 150, (b) an alloy of at least 80 atom percent iron and having aVickers Hardness number of at least 200, and (c) an alloy of at leart 50atom percent (50-79 atom percent) iron and having a Vickers Hardnessnumber of at least 400, preferably the alloy of (a) or (b); themetal-opposing surface of member B comprising a mixture of -90,preferably 25-60, percent by volume of an alloy of at least 6,preferably at least 12, atom percent of an element selected from thegroup consisting of molybdenum and tungsten, at least 10 percent,preferably -85 percent, by volume of the alloy being an intermetalliccompound of said element preferably in the topologically close packedphase, the Vickers Hardness number of the compound being 550-1800, thecoefficient of dry friction of the alloy of member B against the surfaceof member A being no greater than 0.25, and, correspondingly, 90-10(preferably 75- 40) percent by volume of a material having a VickersHardness number less than that of the alloy, the strength and adhesiveproperties of said material being sufficient to support said alloytherein; and the fluid being selected from the group consisting ofpetroleum hydrocarbons having a terminal boiling point no greater than345 C., aliphatic alcohols of 1-12 carbon atoms; and aliphatic aldehydesof 4-9 carbon atoms.

It should be understood that the mixture constituting the opposingsurface of member B may take the form of particles of the molybdenum ortungsten alloy embedded in a matrix of the softer material to form acomposite. The size of the molybdenum or tungsten alloy particles willrange from minus 40 mesh to plus 400 mesh.

Specifically, assemblies of this invention can be formed that meet thecriteria set forth in the previous paragraphs where one of therelatively movable opposing surfaces comprises a mixture of copper andan alloy of 6-85, preferably 19-25 atom percent molybdenum, 4-56,preferably 4-22 atom percent silicon and the balance essentially 10-90atom percent of an element selected from the group consisting of iron,cobalt and nickel, preferably 53-77 atom percent cobalt; the other ofthe relatively movable opposing surfaces comprising an alloy of 1-7 atompercent carbon, up to 13 atom percent chromium and the balanceessentially 80-98 atom percent iron; and the fluid selected from thepreviously stated group but being preferably gasoline. Where thefirst-mentioned relatively movable opposing surface contains an alloy oftungsten, it may be difiicult to incorporate more than atom percent intothe alloy because of the high melting point of tungsten.

It should be understood that in addition to molybdenum and tungsten inthe one opposing surface and iron in the other opposing surface, amountsof elements other than Also containing at least 1 atom percent carbon,the sum of any cobalt and nickel being less than 6 atom percent andwherein at least one-half of the weight of the remainder of the alloy iscomposed of at least one element selected from the group consisting ofchromium, manganese, molybdenum and tungsten, said eloment(s) present asa earbi(le(s) or in n 1 'ully hardened solid solution, e.g., themartensite phase of iron,

those specified above may be used in both surfaces provided that thecriteria regarding the Vickers Hardness numbers, intermetallic compoundand coefiicient of dry friction are met as set forth above. It is alsopossible to include minor amounts of refractory metal oxides in thealloys used such as those disclosed in US. Pat. 3,317,285. In using thesystem of this invention for sliding elements, performance can befurther improved by optimizing the topography, the grooving and theclearance of both surfaces of the sliding couple.

Coefficient of dry friction, as used in the summary of the invention, ismeasured in air, as follows:

A test sample of the alloy containing the intermetallic compound used inmember B is given a metallographic polish and washed with acetone toinsure a smooth clean surface. A ;inch ball or, alternatively, an objecthaving a spherical surface (radius of -inch) near its point of contactwith the flat surface, composed of the material of member A is cleanedby polishing with 600 grit emery cloth. The test sample of the alloy ismounted on a moving track and passed at a speed of 0.001 cm./sec. incontact with the ball of the member A. A load of 1000 grams is imposedon the ball. The frictional drag created by the sample of the alloymoving in contact with the ball is measured by a tangential straingauge. The coefiicient of dry friction is the tangential force requiredto move the test sample divided by the normal force, which in this caseis 1000 grams.

For purposes of simplicity and clarity in illustrating the criticalfeatures of this invention, the discussion will be divided into threesegments:

(1) Metal-contacting or opposing surface of member B, also referred toas the lubricant producing (LP) surface;

(2) Metal-contacting or opposing surface of member A, also referred toas the mating surface; and

(3) Environmental medium, also referred to as the process fluid, carrierfluid or simply, the fluid.

(1) Lubricant producing surface This surface is a composite of arelatively soft material and the molybdenum or tungsten alloy.

The relatively soft materials may be selected from any of the followingfour groups. Group (a) includes the metals copper, nickel, aluminum,lead, tin, cadmium and iron. Group (b) includes alloys of the metals ofgroup (a); lead base alloys such as Babbitt (74.5 lead, 10 tin, 15antimony, 0.5 copper tin base alloys such as Babbitt (91.2 tin, 4.5copper, 4 antimony, 0.3 lead cadmiumbase alloys (97.5 cadmium, 1 nickel,1 silver, 0.5 copper copper base alloys such as tin bronze (88 copper,10 tin, 2 zinc leaded tin bronze (80 copper, 10 lead, 10 tin andcopper-lead copper, 30 lead aluminum base alloys such as (91 aluminum, 7tin, 1 copper, 1 silicon nickel base alloys such as Monel (66 nickel,31.5 copper, 1.3 iron, 0.9 manganese, 0.1 carbon Group (c) includes themetals chromium and molybdenum. Group (d) includes phenolic resins andessentially linear resins having a second order transition temperature(as determined by plots of flexnral modulus versus temperature) of atleast 250 C. and a room temperature modulus of at least 300,000 p.s.i.,e.g., phenolformaldehyde resins, aromatic polyimides, aromaticpolyamides, aromatic polyketones, aromatic polythiazoles andpolybenzotriazoles.

The important criteria for selecting the molybdenum or tungsten alloyare in three distinct areas: chemical composition; physical structure;and physical characteristics. As for chemical composition, the alloyshould contain at least 6 atom percent of molybdenum or tungsten. As forphysical structure, it should be composed of at least 10 percent byvolume of an intermetallic compound having molybdenum or tungsten as acomponent,

2 Parts by weight.

The physical characteristics should be such that the alloy has acoefficient of dry friction when contacted against the mating surface ofno greater than 0.25; the intermetallic compound of the alloy has aVickers Hardness number ranging between 550 and 1800; and the relativelysoft material matrix containing the intermetallic compound should have aVickers Hardness number less than that of the intermetallic compound.

When used in the present invention, the aforementioned alloys will becapable of producing lubricant when subjected to sliding action in thepresence of a fluid capable of being converted into a material havinglubricating properties. It is believed that the soft matrix permitsparticles of the aforementioned alloy to accommodate to any misalignmentbetween surfaces, e.g., shaft and bearing, etc. Thus, superiorcompatibility and superior results are obtained using the composite.Specifically, when subjected to 50,000 PV (load in p.s.i. velocity of180 ft./min. or greater) in the wear tester shown in FIG. 1, the totalwear of both lubricant producing surface (sample) and mating surface(reference ring) will be less than 4.0 mils/100 hrs. as measured bymicrometer or weight measurements; and the coefficient of friction willbe less than 0.2. The test procedure, as set forth hereinafter, wasdesigned so that operating conditions would lead to a state oflubrication below that of the full-fluid range, thus obtainingmetal-to-metal interaction. In this way, the compatibility and abilityof the metal combinations to produce lubricant can be measured. It isbelieved that the lubricant is not Produced continuously in the systemof the invention. Instead, additional lubricant is only produced afterthat originally formed is used.

It is also observed that the softer matrix, e.g., copper, wears awaypreferentially, thereby creating cavities at the sliding interface. Itis believed that these cavities become filled with the environmentalfluid and the lubricant formed. On a micro scale the same phenomenonoccurs within the molybdenum or tungsten alloy in that the softer matrixportion is worn preferentially leaving the hard intermetallic compoundin relief. It is believed that the environmental fluid and the lubricantformed collect in the micro-cavities which are close enough to providesuperior lubrication at the contact points undergoing sliding action.

FIG. 1 is a schematic representation of the wear tester utilized indetermining wear performance. It is representative of end thrust typebearings and is useful as a screening device for determining systems ofthe present invention. The specimen of member A to be tested 12 isrotated by a DC motor 10. The friction between the ring of member B 11and the test specimen of member A 12 produces a torque in the shaft 13.The shaft 13 is constrained from turning by the lever arm 14 connectedto a strain gauge 15. The strain gauge voltage is continuously monitoredon a recorder. This voltage is converted into pounds pull by previouscalibration. From the geometry of the system, the tangential force onthe specimen is calculated. The coeflicient of friction equals thetangential force divided by the normal thrust of load pushing thespecimen and wear ring together. Wear rates are determined from weightloss and also by micrometer measurements. Tests are carried out byrotating the test specimen at a speed of 180 ft./ min. and at varyingloads. The PV is determined by multiplying the load in p.s.i. based uponactual contact area by the speed in ft./min.

Specifically, the specimen 12 and the ring 11 are machine ground toobtain parallel faces and then hand lapped on 400 grit paper; vacuumdried at 100 C. for at least 1 hour; and then weighed to 0.0001 gram andmeasured to 0.0001 inch. They are then mounted in the tester as shown inFIG. 1 and the cup 16 filled with gasoline or other fluid 17. The cup 16is lined with cooling coils to minimize evaporation. Using only theweight of the shaft 13 and lever 14, the tester is run at 650 r.p.m. (toprovide 180 ft./min.) for 1 to 2 minutes. After this period, thepreselected test load is applied and the test is run continuously for 18to 20 hours. Due to evaporation, additional fuel must be added every 4to 6 hours. After 18 to 20 hours, the specimen 12 and the ring 11 areagain vacuum dried; weighed; and measured. Alternatively, the tester maybe loaded in increments of 20 lbs. while being run at the previouslydisclosed speed. The tester may be run 30 minutes at each weightincrement until failure occurs.

The presence of at least 10 volume percent of an intermetallic compoundof molybdenum or tungsten in the contacting surface of member B is vitalto the operability of the present invention. These intermetalliccompounds, in most cases, occur as an intermediate or secondary phasewithin a solid solution or matrix phase. They vary in amount and sizeand are of diverse types. The amount and type is determined by suchfactors as the particular chemistry of the metals being alloyed, thelength of time at which the alloy is subjected to specific temperatureconditions, and the cooling rate. Intermetallic compounds found in thealloys operable in this invention include (1) the topological closepacked (TCP) structures including the sigma, chi, mu and Laves phases,(.2) the semi-carbides of the M C and M C type and (3) Mo Si type. Thepresence and amount of intermetallic compounds may be determined byeither X-ray diffraction or metallographic analysis.

Of primary interest for this invention are the intermetallic compoundsof Laves phase structures characterized by the ternary phase systems,Co-Mo-Si, Ni-Mo-Si, Co-W-Si and Ni-W-Si. These alloys are disclosed inUS. Pat. 3,257,178 to Severns and Smith and represent the most desirablealloys for use as the metal-opposing surface of member B. Specifically,these alloys are defined in this patent as consisting essentially of asubstantial amount of at least one metal A and a substantial amount ofat least one metal B, and silicon, metal A being selected from the groupconsisting of molybdenum and tungsten and metal B being selected fromthe group consisting of cobalt and nickel; and sum of the amounts ofmetals A and B being at least 60 atom percent of the alloy; the amountof silicon and the relative amounts of metals A and B being such as toprovide 30 85 volume percent of said alloy in the Laves phase; the Lavesphase being distributed in a relatively soft matrix of the remaining70-15 volume percent of said alloy.

(2) Mating surface The important criteria for selecting the material forthe mating surface of member A are in two distinct areas: chemicalcomposition and physical characteristics. The particular materials maybe divided into three groups, the first two being preferred.

The first group embraces the cast irons containing graphite. They arethe gray cast irons and malleable cast irons. Carbon content varies from11 to 15 atom percent, and silicon content from 1.5 to 3 atom percentwith the balance being iron and trace amounts of other metals.Hardnesses can be as low as Vickers Hardness number of 150. It isbelieved that the presence of the carbon as graphite offsets the effectof softness. These alloys are useful as piston rings, cylinder walls andin other applications having poor lubrication.

The second group consists of iron alloys containing at least atompercent iron, at least 1 atom percent carbon and having Vickers Hardnessnumbers of at least 200. This group embraces the white cast irons,carbon steels, most of the tool steels and the bottom of the range ofmartensitic stainless steels. It is preferred that the Vickers Hardnessnumber of the steels in this group be over 270.

The third group consists of iron-base alloys containing 50-79 atompercent iron, at least 1 atom percent carbon and having Vickers Hardnessnumbers of at least 400.

Also undesirable are the ferritic stainless steels and most of theaustenitic stainless steels. However, it may be possible to use workhardened low nickel alloys of austenitic stainless steels.

The major alloying element for the second and third groups are chromium,manganese, molybdenum and tungsten. These elements should represent atleast one-half of the weight of the remaining alloying elements (besidesiron and carbon) and should be present primarily as carbide precipitatesor in a fully hardened solid solution, e.g., the martensite phase ofiron. Nickel and cobalt are undesirable and their sum in the alloyshould be less than 6 atom percent.

(3) Environmental medium The most impressive feature of the system ofthis invention is its ability to polymerize certain fluids to formlubricants in situ, thereby obviating the necessity of using anextraneous (non-essential to the function of the system) material suchas heavy petroleum products (e.g., motor oils, lubes, and greases).Because of their commercial interest, the invention is concernedprimarily with systems involving petroleum hydrocarbon fuels as theenvironmental medium. Thus, gasoline in automotive, marine, and aircraftengines; kerosene and jet fuels in modern jet aircraft; and diesel fuelsin diesel type engines are particularly useful in this invention. Thesefluids may be classified as petroleum hydrocarbons whose terminalboiling points are no greater than 345 C. The fluids may be used inliquid or vapor form. One method to achieve the results of the presentinvention is to spray gasoline vapor into the chamber containing therelatively movable opposing surfaces.

It should be noted that as little as weight percent of a fluid operablein this invention in combination wtih 90 weight percent of an inoperablefluid will operate successfully as part of the system of this invention.It should also be pointed out the systems of this invention will operatein the presence of conventional lubricants (solid or fluid) andhydraulic fluids and will thus make possible the use of lesserquantities of such added lubricant. Furthermore, the systems of thisinvention could permit the use of mixtures or dispersions of thespecified hydrocarbons, alcohols and aldehydes with such fluids astrichloroethylene, water, etc. which are not usually consideredlubricants. The use of the systems of this invention make it possible touse hydraulic fluids of relatively low viscosity. During operation, theviscosity of the lubricants produced from these fluids is high enough toperform a lubricating function. In cold weather operation, the viscosityof the hydraulic fluid is low enough so that no heating is required tomaintain fluidity as is usually necessary with more viscous fluids.

USES OF THIS INVENTION The assemblies of this invention findapplicabilitiy in all types of engines: 2- and 4-cycle reciprocatingengines; 2- and 4-cycle rotary engines including the epitrochoidal,elliptical, wedge and vane piston types; free piston gas generatingengines; turbo-jet engines; standard jet engines; and gas turbineengines. Thus, in a 2-cycle reciprocating engine, the bearing surfacesand seals can be composed of or coated with a composite of copper andthe alloy of molybdenum or tungsten referred to herein as member B;while the opposing surfaces including the crankshaft, the pistoncylinder wall, etc. can be composed of the alloy of iron referred toherein as the member A alloy.

The assemblies are also useful in fuel pumps and fuel injectors. Thus,in the fuel injectors the member B composite can be used as a surfacecoating for the plunger which slides through a chamber made of member A,or member B can be used as a coating for the cylinder chamber throughwhich a plunger made of or coated with member A slides. In a fuel pump,the vanes can be coated with or composed of the member B composite whichmakes contact 'with a chamber of member A, or vice versa. This permitsoperation with low viscosity fuels such as gasoline or kerosene. Thisopens up the possibility of operating diesel engines with less viscousfuels than are now used.

A particularly interesting application of the present invention is inthe rotary internal combustion engine described in US. Pat. 3,359,953.This patent describes special techniques to overcome the side sealingproblem. The member B composite of the present invention has been usedon the contacting surface of the end face seals while the inner surfacesof the end walls were composed of member A alloy.

Another interesting application of the present invention is as asolution to the problem of increasing the load bearing capacity of oilimpregnated porous bearings, i.e., self-lubricating bearings. Relativelylarge pores are needed in these bearings to transmit the relativelyviscous lubricant, thereby reducing load bearing capacity. By using alow viscosity precursor that forms a high viscosity lubricant in situ onthe bearing surface, smaller pores would be used. This, in turn,increases the load bearing capacity of the bearing. By using the memberB composite in the bearing along with the environmental media set forthfor this invention, greases having greater viscosity than conventionaloils are produced with an accompanying increase in load bearingcapacity.

To summarize, the assemblies of this invention will be useful in amultitude of situations involving the use of bearings, gears, seals andpistons, the members of the assemblies being used either to form theparts or as coatings for such parts. The following listing of uses isnot intended to be limitative but intended to appraise those skilled inthe art of useful applications of this invention.

LISTING OF END USES I. General bearings II. Specific bearings (1)Internal combustion engines-reciprocating (2) Internal combustionengines-rotary(epitrochoidal,

elliptical, wedge, vane piston) (3) Liquid handling pumps, stirrers, andother chemical processing equipment (4) Hydraulic equipment (5) Vacuumpumps (6) Turbine engines (7) Jet engines (8) Refrigerating equipment(9) Stirling cycle (heat) engine (10) Gas compressors III. Specificgears 1V. Seals Rotary engines Piston ringslnternal combustion enginesChemical pumps Fuel pumps V. Pistons Internal combustion enginesHydraulic equipment F-uel injectors and pumps Positive displacement typefuel pumps It should be noted that in using this system for slidingelements, e.g., seals, journal bearings, etc., performance can beimproved by optimizing the topography, the grooving and the clearance ofboth opposing surfaces of the sliding couple.

The present invention is further illustrated by the following examples.

EXAMPLE 1 A composite was prepared by mixing 100 mesh copper powder with100 +200 mesh alloy 3 of cobalt, molybdenum and silicon in the ratio of50/50 percent by volume. The mixture was plasma sprayed onto an aluminumsubstrate. The composite was then tested in the wear tester shown inFIG. 1 against 1095 steel 4 hardened to a Vickers Hardnes number of 510.A PV of 140,000 was applied to the test specimen and the tester was runfor 6 hours in an environment of gasoline. The gasoline was introducedinto the tester in the form of a spray at a flow rate of 0.42 ml./min.The coefficient of friction was measured and found to be 0.08. At theend of the 6-hour run, the test specimen and the mating surface wereexamined. Not only was there substantially little or no wear evidenced,but also an amber colored product resembling grease was found to bepresent at the interface of contacting surfaces. The average cryoscopicmolecular weight of this reaction product was found to be 420,contrasting with an average molecular weight of 107 for the gasolineinitially introduced.

The lubricity of the reaction product was then measured and comparedwith that of commercially available grease. A small amount of thereaction product was rubbed on a specimen made from 1020 cold rolledsteel. This specimen was then placed in the wear tester and brought intocontact with a reference ring of 1095 steel (Vickers Hardnessnumber=5l0). The combination of 1095 steel against 1020 steel wouldnormally seize immediately in a gasoline environment. In the presence ofthe reaction product, however, which was smeared on the surfaceinterface between the two steels, the tester ran smoothly at a PV of200,000; the wear rate was low; and the coefficient of friction was0.036, identical to that ob- 3 56 atom percent cobalt, 22 atom percentmolybdenum and 22 atom percent silicon.

95.7 atom percent iron, 4.3 atom percent carbon.

5 0.9 atom percent carbon, 0.5 atom percent manganese, 98.6 atom percentiron (all nominal).

10 tained when a commercial grade lubricating grease was employed. Incontrast, when Vaseline, a less effective lubricant was substituted, thecoefficient of friction increased to 0.08 at a PV of only 55,000. Themeasured wear rate was correspondingly high.

EXAMPLES 2-8 A series of iron alloys as member A and composites ofvarious matrix materials and alloys of molybdenum or tungsten as memberB was prepared and tested in the Wear tester shown in FIG. 1 followingsubstantially the procedure set forth in Example 9. Gasoline was used asthe environmental medium in Examples 2-6; n-octane, in Example 7 andhexanol, in Example 8.

The alloy used as member A and its Vickers Hardness number (V.H.) andthe composite used as member B are shown in Table I-A and the resultsare shown in Table I-B.

TABLE I-A Member B, alloymatrix material (volume percent) Member AExample:

2 1095 steel CM 5535 60 copper, 20 nickel. 3 Elastufi 44 CM 5535 nickel.4* .do 25 CM 5535 polyimide. d 5- 1095 steel 20 NW 4540 copper. 6-

35 CM 553565 copper. 7. 35 NW 4540-65 copper. 8. 35 CM 5535-65 copper.

95.7 at, percent Fe, 4.3 at. percent C (V.H. 516). 56.4 at. percent Co,22.1 at. percent Mo, 21.5 at percent Si s 93.6 at. percent Fe, 2.1 at.percent C, 1.7 at. percent S, 1 at. percent Cr, .9 at. percent Mn, 0.4at. percent Si, 0.3 at. percent Mo (VII. 434).

d polymer of 4,4oxydianiline and pyrornellitic dianhydride.

50.7 at. percent Ni, 14.5 at. percent W, 34.8 at. percent Si.

80 at. percent Fe, 12 at. percent Cr, 6.6 at. percent C, 1 at. percentV, 0.4 at. percent Mo NH. 720) Cold pressing and heated to a temperatureof ZOO-500 C.

TABLE I-B Total wear (mils/100 hrs.) PV Coefiicient Example X 1,000 offriction Mem. A Mem. B

EXAMPLE 9 FIG. 2 illustrates a device utilized to test the efficiency ofcertain type bearings intended for commercial applications. Referring tothis schematic sketch, friction between shaft 61 and the bearing to betested 62 causes a yolk 63 to rotate when a load 64 is applied. Therotation of the yolk applies a force to a torque transducer 65 throughlever arm 66. From the torque which is recorded on a chart recorder, notshown, the tangential force acting at the bearing shaft interface iscalculated. This divided by the load applied gives the coefiicient offriction. The transducer is calibrated before each test. The processfluid, is introduced into the bearing system through port 67.

The test procedure involves increasing the flow of gasoline to 1 lb. perhour at no load and then increasing the rpm. of the shaft to the desiredlevel. The load is applied in increments of 20 lb. and the apparatusallowed to run from 30 minutes to an hour at each step.

A composite was prepared by pressing mesh copper powder with 28 volumepercent of an alloy consisting of 56 atom percent cobalt, 22 atompercent molybdenum and 22 atom percent silicon (l00 mesh +200 mesh).After heating the composite to 850 C. in hydrogen, billets were forgedin air to a diameter of 1% inches. After heat treatment at 850 C. inhydrogen for 3-4 hours to promote bonding between copper and the alloy,journals were rough machined using carbide tools to Within 10 TABLEII.--COEFFICIENT OF FRICTION AT VARIOUS LOADINGS (PV) PV (p.s.i. XItJmin.)

Example 9 0. 004 0. 006 0. 007 0. 004

Control A- 0.21 0.16 0.16 0.16

Control B Seized Seized Seized Seized Seized EXAMPLE 10 A 2-cycle enginewas modified as shown in FIG. 3 to permit operation without addition ofoil to the fuel system. The original engine was a 2-cycle, 2% horsepowerengine Model D-402 manufactured by the Outboard Marine Corp., Galesburg,Ill. The clearances after modifications of the bearings, piston, andpiston rings were the maximum allowable falling within thespecifications of the manufacturer. In addition, the sleeve bearingswere grooved to direct the gasoline to the bearing interfaces.

The sleeve bearings 21 and 22 used as magneto platebearings and shaftbearings were made from composites of copper and 28 percent by volume ofthe alloy 8 used in Example 1. These hearings were sealed at both endsto prevent gasoline from passing directly into the aluminum crankcase. Ahardened low alloy steel within the definition of member A of theinvention was used as the crankshaft 24. The piston 29 was coated with amixture of copper and 25 percent by volume of the allow of Example 1 byplasma spraying to a thickness of .004.005 inch. The particular sizeused in these coatings was -l00 mesh and 200 mesh. A band of thiscoating was put at the top and bottom of the piston, although it ispreferable to coat the entire piston. This piston rings 28 which slideagainst the cast iron cylinder walls were the manufacturers cast ironrings coated with the alloy of Example 1 by plasma spraying.

Although the fuel pump was electrically operated, it may be operated asa positive displacement diaphragmtype fuel pump as shown in FIG. 3. Theflow of fuel (gasoline) is designated by the dotted lines. Fuel from thetank 31 is sucked into the fuel pump 30. From here, it is pumped intobearing 22, removed from a port on the opposite side, and passed intothe cast-iron cylinder 32 through port 33 and other similar orthogonalports not shown. The fuel flowing into port 33 lubricates bearings 26and 27 in the following manner. Hollow wrist pin 25 is blocked at oneend to prevent fuel from passing through it and out the exhaust port 34.When the wrist pin 25 passes over the port 33, gasoline is ejected intoit and flows towards the exhaust end. Since this end is blocked andbearings 26 and 27 are provided with openings, this gasoline flows intothese bearings for lubrication. Not shown in FIG. 3 are the openings inthe bottom of bearing 27 and in the top of bearing 26 to allow 90 atompercent copper, 4 atom percent tin, 4 atom percent zinc, and 2 atompercent lead.

7 93.2 atom percent iron, 4.4 atom percent carbon, 1.5 atom percentchromium, 0.6 atom percent silicon, 0.3 atom percent manganese.

B 56 atom percent cobalt, 22 atom percent molybdenum and 22 atom percentsilicon.

12' gasoline vapor in the crankcase 36 to provide additional lubricationto bearings 26 and 27.

Fuel may also be pumped from pump 30 into bearing 21. It then flows downthis bearing as indicated and through and opening 35 in the crankshaft24 to lubricate bearing 23. Bearing 23 is a roller bearing having anouter race of an alloy (77 atom percent cobalt, 19 atom percentmolybdenum and 4 atom percent silicon). The crankshaft served as aninner race and the manufacturers needles (52100 steel) were used asrolling elements.

The fuel is ejected from bearing 23 into the crankcase chamber 36. Fuelis also pumped into the carburetor 37. The reed valve 38 on thecarburetor closes when the crankcase 36 is under compression and openswhen the crankcase is under a low pressure, i.e., when the piston 39 isin its highest position. Although not shown on the figure, there areports for channeling the gasoline-air mixture into the combustionchamber 40. Flow of fuel through the carburetor 37 is controlled by theamount of air sucked into the engine. This amount of air, in turn, iscontrolled by a governor.

It was found that for smooth engine operation it was desirable that atleast 50 percent of'the fuel passed through the normal combustion route,i.e., through the carburetor and into the combustion chamber on theupstroke of the piston. The control of the amount of flow of gasolinethrough the carburetor 37 and to bearings 21, 22 and 23 is accomplishedby needle valves.

In the test run, the pump 30 was started to admit fuel to all bearingsurfaces just prior to starting the engine. Thus, the hearings were notoperated in the dry condition. The engine was then run for 50 hoursusing commercially available permium gasoline containing no oil. Thefuel was introduced into the engine at a rate of 2.1 lbs/hr. The airflow was 19 lbs./hr. giving an air-fuel ratio of about 9 to l. Theengine speed was 2,450 rpm. No load was placed on the engine. Duringoperation, there was no visible smoke in the exhaust as occured duringoperation of the unmodified 2-cycle engine run on the fuel-oil mixturerecommended by the manufacturer. Other than a thin sooty deposit thatcovered the piston and cylinder walls, there were no engine deposits.The dimensions of the essential friction wear parts were measured beforeand after the test to determine the amount of wear. The results aretabulated in Table III.

TABLE III.DIMENSIONS OF ESSENTIAL FRICTIONWEAR PARTS BEFORE AND AFTER 50HOUR ENGINE TEST Where engine designs are such that oil must be presentto insure lubrication of certain surfaces, it is possible by use of thelubricant-producing surfaces of this invention to greatly reduce theamount of oil that must be supplied. For example, the 2-cycle enginedescribed above has been run, without introducing fuel through thecylinder wall, by using instead of the pure gasoline a mixture of 1 partof SAE 30 oil in 500 parts of gasoline. With the usual sliding surfacesin the combustion chamber a ratio of 1 part of standard oil in 16 partsof gasoline is required.

932 at. percent Fe, 4.4 at. percent C, 1.5 at. percent Cr, 0.6 at.percent Si, 0.3 at. percent Mn.

When a completely unmodified 2-cycle engine of a similar design was runon a gasoline-oil (16-1 ratio) mixture for 32 hours, the exhaust portswere almost completely clogged with heavy deposits of carbon. Furtherrunning of this engine would require disassembly and cleaning of ports,piston and cylinder.

EXAMPLE 11 One of the most promising potential end uses for the presentinvention would 'appear to be as seals in rotary engines. A sequence oftests to evaluate the performance of the system of this invention asseals in the engine described in US. Pat. 3,359,953 (the Wankel engine)was initiated. For this, a Gast air motor was used, as illustrated inFIG. 4. Normally, this engine would be powered by compressed airinjected through the inlet. For these experiments, however, the motorwas driven by means of bearing tester described for use in FIG. 2 Themotor of the bearing tester was attached to the rotary shaft of the airmotor by a coupling causing the air motor to rotate.

In the first test, vanes 51 made from a composite of copper and 30percent by volume of the alloy of Example 1 were compared to hardchromium plated vanes. The test was run at room temperature. The motorwas driven at 1200 r.p.m. while 0.1 lb. per hour of commerciallyavailable premium grade gasoline was flushed through it with 1 lb. perhour of nitrogen. This low amount of gasoline was used to more closelysimulate the amount of unburned fuel in an engine. In a 3.5 hour run thechromium plated vanes ruined the cast-iron housing and generated enoughwear debris to plug the outlet port. In the same period, no wear of thevanes or housing could be measured when the vanes were made from thecomposite described in Example 9. Next, the test on the vanes of thiscomposite was repeated except that the housing was heated to 150 C., thehighest surface temperature reached in the Wankel engine. Again, no wearof the composite vanes or housing could be measured. After the test allinterior surfaces were coated with a substance corresponding inviscosity to SAE -30 grade commercial oil, indicating formation of alubricant in situ when in continuous contact with gasoline.

EXAMPLE 12 To demonstrate a gasoline pump using the system of thisinvention, the vanes in a Gast air motor were replaced with vanesprepared from the composite set forth in Example 11. The motor wasoperated as a pump by driving it with bearing tester of FIG. 2 at 1200r.p.m. Gasoline was pumped at a rate of gal/hr. in a closed loop with aone gallon reservoir for 5.25 hours. No wear on the vanes could bemeasured and the weight loss per vane averaged one milligram.

Wankel engine using an aluminum housing.

What is claimed is:

1. A system comprising an assembly of at least two members, members Aand B, having relatively movable opposing surfaces and an environmentalfluid capable of forming a lubricating medium for said opposing surfacesduring operation of the assembly; the opposing surface of member Aconsisting essentially of an alloy selected from the group consisting of(a) an alloy of 11-15 atom percent carbon, 1.5-3 atom percent siliconand the balance being su-bstantially all iron, and having a VickersHardness number of at least 150, (b) an alloy of at least 80 atompercent iron, at least 1 atom percent carbon, and having a VickersHardness number of at least 200, and (c) an alloy of 50-79 atom percentiron, at least 1 atom percent carbon, and having a Vickers Hardnessnumber of at least 400, the sum of any cobalt and nickel in said alloys(b) and (0) being less than 6 atom percent, at least one-half of theweight of the remainder of alloys (b) and (c) being selected from thegroup of elements consisting of chrominum, molybdenum, manganese andtungsten, said element(s) being present as carbide(s) or in a fullyhardened solid solution; the opposing surface of member B consistingessentially of a mixture of 10-90 volume percent of an alloy of at least6 atom percent of an element selected from the group consisting ofmolybdenum and tungsten, at least 10 percent by volume of said alloybeing an intermetallic compound of said element, the Vickers Hardnessnumber of said compound being 550-1800, the coefiicient of dry frictionof said alloy of member B against the surface of member A being nogreater than 0.25 and, correspondingly, 90-10 percent by volume of amaterial having a Vickers Hardness number less than that of said alloy,the strength and adhesive properties of said material being suificientto support said alloy therein; and said environmental fluid beingselected from the group consisting of petroleum hydrocarbons having aterminal boiling point no greater than 345 -C., aliphatic alcohols of1-12 carbon atoms and aliphatic aldehydes of 4-9 carbon atoms.

2. A system as in claim 1 wherein said opposing surface of member A isan alloy of 11-15 atom percent carbon, 1.5-3 atom percent silicon, thebalance being substantially all iron, having a Vickers Hardness numberof at least 150.

3. A system as in claim 1 wherein said opposing surface of member A issaid alloy of at least atom percent iron having a Vickers Hardnessnumber of at least 200.

4. A system as in claim 11 wherein the alloy of the mixture in theopposing surface of member B is an alloy of at least 12 atom percent ofan element selected from the group consisting of molybdenum andtungsten.

5. A system as in claim 4 wherein said element is molybdenum.

6. A system as in claim 4 wherein said element is tungstem.

7. A system as in claim 1 wherein the alloy of the mixture in theopposing surface of member B consists essentially of 6-85 atom percentmolybdenum, 4-56 atom percent silicon, the balance being selected fromthe group consisting of iron, cobalt and nickel.

-8. A system as in claim 1 wherein the alloy of the mixture in theopposing surface of member B consists essentially of 19-25 atom percentmolybdenum, 4-22 atom percent silicon and 53-77 atom percent cobalt.

9. A system as in claim 1 wherein the intermetallic compound in thealloy of said opposing surface of member B is 20-85 percent by volume ofth alloy.

10. A system as in claim 1 wherein said environmental fluid is apetroleum hydrocarbon having a terminal boiling point no greater than345 C.

11. A system as in claim 1 wherein said environmental fluid is gasoline.

12. A system as in claim 14 wherein said environmental fluid isgasoline.

13. A system as in claim 1 wherein oil is added to said environmentalfluid.

14. A system as in claim 1 wherein said material in the mixture having aVickers Hardness number less than that of said alloy is selected fromthe groups consisting of (a) copper, nickel, aluminum, lead, tin,cadmium and iron, (b) alloys of the metals of group (a), (c) chromiumand molybdenum, and (d) polyimides, aromatic polyamides, aromaticpolyketones, polybenzimidazoles, arornatic polyimines,polybenzotriazoles, aromatic polythiazoles, phenol-formaldehyde resin.

15. A system as in claim 1 wherein said material is copper.

16. A system as in claim 1 wherein said material is a copper alloy.

17. A system as in claim 1 wherein said material is nickel.

18. A system as in claim 1 wherein said material is a polyirnide ofpyromellitic dianhydride and 4,4 oxydianiline.

19. An assembly comprising at least two members,

members A and B, having relatively movable opposing surfaces; theopposing surface of member A consisting essentially of an alloy selectedfrom the group consisting of (a) an alloy of 11-15 atom percent carbon,1.5-3 atom percent silicon and the balance being substantially all iron,and having a Vickers Hardness number of at least 150, (b) an alloy of atleast 80 atom percent iron, at least 1 atom percent carbon, and having aVickers Hardness number of at least 200, and (c) an alloy of 50-79 atompercent iron, at least 1 atom percent carbon, and having a VickersHardness number of at least 400, the sum of any cobalt and nickel insaid alloys (b) and being less than 6 atom percent, at least onehalf ofthe weight of the remainder of alloys (b) and (0) being selected fromthe group of elements consisting of chromium, molybdenum, manganese andtungsten, said element(s) being present as carbide(s) or in a fullyhardened solid solution; and the opposing surface of member B consistingessentially of a mixture of 10-90 volume percent of an alloy of at least'6 atom percent of an element selected from the group consisting ofmolybdenum and tungsten, at least 10 percent by volume of said alloybeing an intermetallic compound of said element, the Vickers Hardnessnumber of said compound being 550-1800, the coefficient of dry frictionof said alloy of member B against the surface of member A being nogreater than 0.25, and, correspondingly, 90-10 volume percent of amaterial having a Vickers Hardness number less than that of said alloy,the strength and adhesive properties of said material being sufficientto support said alloy therein.

20. An assembly as in claim 19 wherein said opposing surface of member Ais an alloy of llatom percent carbon, 1.5-3 atom percent silicon, thebalance being substantially all iron, having a Vickers Hardness numberof at least 150.

21. An assembly as in claim 19 wherein said opposing surface of member Ais said alloy of at least 80 atom percent iron having a Vickers Hardnessnumber of at least 200.

22. An assembly as in claim 19 wherein the alloy of the mixture in theopposing surface of member B is an alloy of at least 12 atom percent ofan element selected from the group consisting of molybdenum andtungsten.

23. An assembly as in claim 22 wherein said element is molybdenum.

24. An assembly as in claim 22 wherein said element is tungsten.

25. An assembly as in claim 19 wherein the alloy of the mixture in theopposing surface of member B consists essentially of 6-85 atom percentmolybdenum, 4-56 atom percent silicon, the balance being selected fromthe group consisting of iron, cobalt and nickel.

26. An assembly as in claim 19 wherein the alloy of the mixture in theopposing surface of member B consists essentially of 19-25 atom percentmolybdenum, 4-22 atom percent silicon and 53-77 atom percent cobalt.

27. An assembly as in claim 19 wherein the intermetallic compound in thealloy of said opposing surface of member B is -85 percent by volume ofthe alloy.

28. An assembly as in claim 19 wherein said material in the mixturehaving a Vickers Hardness number less than that of said alloy isselected from the groups consisting of (a) copper, nickel, aluminum,lead, tin, cadmium and iron, (b) alloys of the metals of group (a), (c)chromium and molybdenum, and (d) polyimides, aromatic polyamides,aromatic polyketones, polybenzimidazoles, aromatic polyiinines,polybenzotriazoles, aromatic polythiazoles, phenol-formaldehyde resin.

29. An assembly as in claim 19 wherein said material is copper.

30. An assembly as in claim 19 wherein said material is a copper alloy.

31. An assembly as in claim 19 wherein said material is nickel.

32. An assembly as in claim 19 wherein said material is a polyimide ofpyromellitic dianhydride and 4,4 oxydianiline.

33. A process for forming a lubricating medium which comprises placingthe surfaces of at least two members, members A and B, in opposition,the opposing surface of member A consisting essentially of an alloyselected from the group consisting of (a) an alloy of 11-15 atom percentcarbon, 1.5-3 atom percent silicon and the balance being substantiallyall iron, and having a Vickers Hardness number of at least 150, (b) analloy of at least atom percent iron, at least 1 atom percent carbon, andhaving a Vickers Hardness number of at least 200, and (c) an alloy of50-79 atom percent iron, at least 1 atom percent carbon, and having aVickers Hardness number of at least 400, the sum of any cobalt andnickel in said alloys (b) and (c) being less than 6 atom percent, atleast one-half of the weight of the remainder of alloys (b) and (c)being selected from the group of elements consisting of chromium,molybdenum, manganese and tungsten, said element(s) being present ascarbide(s) or in a fully hardened solid solution; and the opposingsurface of member B consisting essentially of a mixture of 10-90 volumepercent of an alloy of at least 6 atom percent of an element selectedfrom the group consisting of molybdenum and tungsten, at least 10percent by volume of said alloy being an intermetallic compound of saidelement, the Vickers Hardness number of said compound being 550- 1800,the coefficient of dry friction of said alloy of member B against thesurface of member A being no greater than 0.25, and, correspondingly,-10 percent by volume of a material having a Vickers Hardness numberless than that of said alloy, the strength and adhesive properties ofsaid material being sufficient to support said alloy therein; adding afluid in a manner such that it flows onto the opposing surfaces ofmembers A and B, said fluid being selected from the group consisting ofpetroleum hydrocarbons having a terminal boiling point no greater than345 C., aliphatic alcohols of 1-12 carbon atoms and aliphatic aldehydesof 4-9 carbon atoms; and moving said opposing surfaces relative to eachother whereby said fluid is polymerized to form a lubricating medium.

34. A process as in claim 33 wherein an oil is added with said fluid.

35. In a lubricating system composed of the opposing surfaces of atleast two members, members A and B, and a lubricating fluid present onsaid opposing surfaces, the improvement wherein the opposing surface ofmember A consists essentially of an alloy selected from the groupconsisting of (a) an alloy of ll-15 atom percent carbon, 1.5-3 atompercent silicon, the balance being substantially all iron, having aVickers Hardness number of at least 150, (b) an alloy of at least 80atom percent iron and having a Vickers Hardness number of at least 175,and (c) an alloy of at least 50 atom percent iron and having a VickersHardness number of at least 400, the sum of any cobalt and nickel insaid alloys (b) and (c) being less than 6 atom percent, at leastone-half of the weight of the remainder of alloys (b) and (c) beingselected from the group of elements consisting of chromium, molybdenum,manganese and tungsten, said element(s) being present as carbide(s) orin a fully hardened solid solution; and the opposing surface of member Bconsists essentially of a mixture of 10-90 volume percent of an alloy ofat least 6 atom percent of an element selected from the group consistingof molybdenum and tungsten, at least 10 percent by volume of said alloybeing an intermetallic compound of said element, the Vickers Hardnessnumber of said compound being 550-1800, the coeflicient of dry frictionof said alloy of member B against the surface of member A being nogreater than 0.25, and, correspondingly, 90-10 percent by volume of amaterial having a Vickers Hardness number less than that of said alloy,the strength and adhesive properties of said material being sufficientto support said alloy therein.

(References on following page) 17 18 References Cited 3,217,834 11/1965Nakamura 1841 3,283, U ITED STATES PATENTS O29 11/1966 Brllland et al208 4/1941 Pratt et a1. HERBERT LEVINE, Prlmary Exarnmer 4/1941 Frolichet a1. 208--19 5 U.S. Cl. X.R. 3/1954 Stratford et 23----285; 123 s,196; 184- 1, 5;20s- 1s, 19; 252-42; 7/1965 Devine et a1. 1841 260-601,432,, 695; 264--68

